The use of video systems by the U.S. Navy is well established. It has become standard practice to transmit image information over varying lengths of telemetry connections to television monitors. Such systems and techniques are finding widespread application in undersea systems.
Besides transmitting image information, a television camera also transmits timing pulses, called synchronizing pulses, which are used for horizontal and vertical synchronization by the television monitor. These timing pulses occur in intervals, called blanking intervals, outside the normal television monitoring viewing area. Also, these pulses are of sufficient duration and repetition rate such that they can be used as carriers for additional information bearing signals.
In addition to video information transmitted over telemetry links, digital information bearing signals are also extensively utilized for carrying data and can be transmitted over long telemetry cabled systems. It is the intent of this invention to combine the two requirements, transmitting video data as well as transmitting digital information, into one signal transmitted via a telemetry link.